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pls help wif this circuit...urgent

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rishi_azzuris

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i need to get 100watts out of this circuit but the output power of this circuit is only 20-40watts. it has to be 144MHz circuit as well. what if i don't use the transistors stated in the circuits and use the mrf247 transistor which will give me 100watts output, will the circuit work? the data sheet of the mrf247 is below as well. if anybody out there who knows any other transistor which suits the circuit below and will give me 100 watts output, pls let me know. i've already tried cascading it, but it doesn't seem to work. if anybody has a 2meter band(144MHz) PA circuit, pls send it to me.. it must have 80-110watts output power. thank you
 

throwaway18

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You don't say if you want a class C amp for FM or a linear amp for SSB.

A single transistor can supply a limited amount of gain. x10 power gain per stage is about the most that can be done without oscillation.

i've already tried cascading it, but it doesn't seem to work

If your amp is only capable of 40watts then excessive input power will only damage it.

12V is marginal for 100W with a single transistor.

Learn to search. Here are a couple of 100X 2m amp designs I just found with google.

https://perso.wanadoo.fr/f6itv/p2032001.htm
https://hjem.get2net.dk/ole_nykjaer/oz2oe/mrf317/317.html
 

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